/*
* Sets up interrupt handlers for various hardware switches which are
* connected to interrupt lines.
*
* Copyright 2005-2207 PMC-Sierra, Inc.
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License as published by the
* Free Software Foundation; either version 2 of the License, or (at your
* option) any later version.
*
* THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN
* NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
* USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
* ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write to the Free Software Foundation, Inc.,
* 675 Mass Ave, Cambridge, MA 02139, USA.
*/
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/interrupt.h>
#include <msp_int.h>
#include <msp_regs.h>
#include <msp_regops.h>
/* For hwbutton_interrupt->initial_state */
#define HWBUTTON_HI 0x1
#define HWBUTTON_LO 0x2
/*
* This struct describes a hardware button
*/
struct hwbutton_interrupt {
char *name; /* Name of button */
int irq; /* Actual LINUX IRQ */
int eirq; /* Extended IRQ number (0-7) */
int initial_state; /* The "normal" state of the switch */
void (*handle_hi)(void *); /* Handler: switch input has gone HI */
void (*handle_lo)(void *); /* Handler: switch input has gone LO */
void *data; /* Optional data to pass to handler */
};
#ifdef CONFIG_PMC_MSP7120_GW
extern void msp_restart(char *);
static void softreset_push(void *data)
{
printk(KERN_WARNING "SOFTRESET switch was pushed\n");
/*
* In the future you could move this to the release handler,
* timing the difference between the 'push' and 'release', and only
* doing this ungraceful restart if the button has been down for
* a certain amount of time; otherwise doing a graceful restart.
*/
msp_restart(NULL);
}
static void softreset_release(void *data)
{
printk(KERN_WARNING "SOFTRESET switch was released\n");
/* Do nothing */
}
static void standby_on(void *data)
{
printk(KERN_WARNING "STANDBY switch was set to ON (not implemented)\n");
/* TODO: Put board in standby mode */
}
static void standby_off(void *data)
{
printk(KERN_WARNING
"STANDBY switch was set to OFF (not implemented)\n");
/* TODO: Take out of standby mode */
}
static struct hwbutton_interrupt softreset_sw = {
.name = "Softreset button",
.irq = MSP_INT_EXT0,
.eirq = 0,
.initial_state = HWBUTTON_HI,
.handle_hi = softreset_release,
.handle_lo = softreset_push,
.data = NULL,
};
static struct hwbutton_interrupt standby_sw = {
.name = "Standby switch",
.irq = MSP_INT_EXT1,
.eirq = 1,
.initial_state = HWBUTTON_HI,
.handle_hi = standby_off,
.handle_lo = standby_on,
.data = NULL,
};
#endif /* CONFIG_PMC_MSP7120_GW */
static irqreturn_t hwbutton_handler(int irq, void *data)
{
struct hwbutton_interrupt *hirq = data;
unsigned long cic_ext = *CIC_EXT_CFG_REG;
if (CIC_EXT_IS_ACTIVE_HI(cic_ext, hirq->eirq)) {
/* Interrupt: pin is now HI */
CIC_EXT_SET_ACTIVE_LO(cic_ext, hirq->eirq);
hirq->handle_hi(hirq->data);
} else {
/* Interrupt: pin is now LO */
CIC_EXT_SET_ACTIVE_HI(cic_ext, hirq->eirq);
hirq->handle_lo(hirq->data);
}
/*
* Invert the POLARITY of this level interrupt to ack the interrupt
* Thus next state change will invoke the opposite message
*/
*CIC_EXT_CFG_REG = cic_ext;
return IRQ_HANDLED;
}
static int msp_hwbutton_register(struct hwbutton_interrupt *hirq)
{
unsigned long cic_ext;
if (hirq->handle_hi == NULL || hirq->handle_lo == NULL)
return -EINVAL;
cic_ext = *CIC_EXT_CFG_REG;
CIC_EXT_SET_TRIGGER_LEVEL(cic_ext, hirq->eirq);
if (hirq->initial_state == HWBUTTON_HI)
CIC_EXT_SET_ACTIVE_LO(cic_ext, hirq->eirq);
else
CIC_EXT_SET_ACTIVE_HI(cic_ext, hirq->eirq);
*CIC_EXT_CFG_REG = cic_ext;
return request_irq(hirq->irq, hwbutton_handler, 0,
hirq->name, hirq);
}
static int __init msp_hwbutton_setup(void)
{
#ifdef CONFIG_PMC_MSP7120_GW
msp_hwbutton_register(&softreset_sw);
msp_hwbutton_register(&standby_sw);
#endif
return 0;
}
subsys_initcall(msp_hwbutton_setup);
